Convert mixed number to improper fraction:

The addition property of equality justifies this. You could also say that she simply subtracted 7, and then it would be the subtraction property of equality. This is the case because if you add or subtract (or multiply or divide) the same number on both sides of an equation, the equation will still be the same.
Hope it helps!
For this case we have the following expression:

For simplicity we follow the steps:
We apply distributive property to the terms within the parenthesis, bearing in mind that:

We add similar terms taking into account that equal signs are added and the same sign is placed, while different signs are subtracted and the sign of the major is placed.

ANswer:

X is each friend
3x + 28 > 200
3x > 172
x > $57.33
Answer: 4 years
Step-by-step explanation:
Your question isn't complete but I believe that you want to calculate the number of years. This will be:
Simple Interest = PRT/100
where,
Interest = 864 - 800 = 64
Principal = 800
Rate = 2%
Therefore, 64 = 800 × 2 × T /100
Cross multiply
64 × 100 = 1600T
6400 = 1600T
T = 6400/1600
T = 4
Therefore, time will be 4 years